src/java.base/share/classes/java/nio/file/FileStore.java

*** 1,7 ****
  /*
!  * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2007, 2017, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
*** 110,119 ****
--- 110,143 ----
       *          if an I/O error occurs
       */
      public abstract long getUsableSpace() throws IOException;
  
      /**
+      * Returns the number of bytes per block in this file store.
+      *
+      * <p> File storage is typically organized into discrete sequences of bytes
+      * called <i>blocks</i>. A block is the smallest storage unit of a file store.
+      * Every read and write operation is performed on a multiple of blocks.
+      *
+      * @implSpec The implementation in this class throws an
+      *         {@code UnsupportedOperationException}.
+      *
+      * @return  the block size of this file store, in bytes
+      *
+      * @throws  IOException
+      *          if an I/O error occurs
+      *
+      * @throws  UnsupportedOperationException
+      *          if the operation is not supported
+      *
+      * @since 10
+      */
+     public long getBlockSize() throws IOException {
+         throw new UnsupportedOperationException();
+     }
+ 
+     /**
       * Returns the number of unallocated bytes in the file store.
       *
       * <p> The returned number of unallocated bytes is a hint, but not a
       * guarantee, that it is possible to use most or any of these bytes.  The
       * number of unallocated bytes is most likely to be accurate immediately